3-Butene-1-ol prepared by electrocatalytic hydrodehydroxylation of 1,4-butenediol and its preparation method and application

Abstract

The invention discloses a 3-butene-1-alcohol prepared based on electrocatalytic 1,4-butenediol hydrogenation and dehydroxylation and its preparation method and application, relating to the field of organic synthesis technology. The method adopts a flow-type / H-type electrolyzer to add 1,4-butenediol to the cathode electrolyte, using water as a hydrogen source, and realizes the highly selective preparation of 3-butene-1-alcohol by a three-electrode or two-electrode method under the action of a catalyst. The method is a green, safe, low-cost, and highly efficient electrocatalytic method. Compared with the traditional thermal catalytic route, the reaction energy consumption is reduced, the reaction conditions are mild and environmentally friendly, and the raw material cost is low, the substrate conversion rate and product selectivity are high, the process cost is low, and the requirements of green chemical industry are met, which has great development prospects and strategic significance.

Description

Technical Field

[0001] The present invention relates to the technical field of organic synthesis, and in particular to 3-butene-1-ol prepared by electrocatalytic hydrodehydroxylation of 1,4-butenediol, and a preparation method and application thereof. Background Art

[0002] 3-Butene-1-ol (BTO) is an unsaturated alcohol containing a double bond and a hydroxyl group. Its chemical properties are highly active, allowing it to participate in a variety of reactions, including oxidation, reduction, addition, and esterification. BTO is widely used in fine chemicals, including pharmaceuticals, pesticides, plastic lenses, edible flavors, and petroleum processing. For example, as an important pharmaceutical intermediate, BTO can be used to synthesize new heterocyclic derivatives, including anti-AIDS, anti-tumor, and anti-proliferative drugs.

[0003] To date, the main industrial methods for synthesizing 3-butene-1-ol include the propylene formaldehyde addition method, the 3-butenoic acid reduction method, the 3-butyne-1-ol hydrogenation method, and the 1,4-butanediol selective dehydration method. The propylene formaldehyde addition method uses propylene and formaldehyde as raw materials, and synthesizes them at temperatures of 235-350°C and pressures of 50-800 bar, catalyzed by ethanol and silica sand, achieving a yield of 27%. However, this method requires high energy consumption and product separation is difficult. The 3-butenoic acid reduction method uses lithium aluminum tetrahydride as a reducing agent for chemical reduction, but this reducing agent is expensive and highly flammable, which poses a risk to safe and economic production. The 3-butyne-1-ol hydrogenation method uses 3-butyne-1-ol and hydrogen as raw materials, and obtains it through thermal catalytic hydrogenation in an alcoholic solvent. However, this method uses expensive raw materials, and the hydrogen gas poses an explosion risk. The selective dehydration method for 1,4-butanediol was proposed by Japanese researchers Sato et al. (Catal. Commun., 2003, 4: 77). 1,4-Butanediol is first vaporized at high temperatures (>300°C) and then dehydrated over a solid oxide catalyst (such as cerium oxide or indium oxide). This method is relatively economical and efficient, but it also inevitably produces a series of byproducts, such as BDO cyclization to tetrahydrofuran (THF) or γ-butyrolactone (GBL), or isomerization, hydrogenation, and dehydrogenation to produce byproducts such as 2-butene-1-ol, 2-butanal, and n-butanol. The reaction also requires high temperatures.

[0004] Therefore, there is an urgent need to develop a low-energy, low-cost, and environmentally friendly efficient technology route. Summary of the Invention

[0005] To address the shortcomings of the aforementioned background technology, the present invention primarily addresses the existing BTO synthesis routes, which still suffer from harsh reaction conditions, high raw material costs, and complex product separation. Most routes require relatively high temperatures and pressures, resulting in high energy consumption and high carbon dioxide emissions. The present invention provides a method for preparing 3-butene-1-ol by electrocatalytic hydrodehydroxylation of 1,4-butenediol. This method utilizes electricity generated by renewable energy at room temperature and pressure, resulting in low energy consumption. Furthermore, it uses inexpensive water and 1,4-butenediol as raw materials, resulting in low cost and a safe reaction.

[0006] The first object of the present invention is to provide a method for preparing 3-butene-1-ol by electrocatalytic hydrodehydroxylation of 1,4-butenediol, comprising the following steps:

[0007] Adhere cathode or anode powder catalyst to the conductive substrate by adopting in-situ growth method or powder spraying method to prepare cathode or anode;

[0008] A flow electrolytic cell or an H-type electrolytic cell is assembled using the prepared cathode and anode, and a cathode electrolyte and an anode electrolyte are introduced into the cathode chamber and the anode chamber, respectively. At the same time, the raw material 1,4-butenediol is introduced into the cathode chamber. Subsequently, a three-electrode or two-electrode system is used to carry out an electrochemical hydrogenation-dehydroxylation reaction of 1,4-butenediol. After 1-2 hours of electrochemical reaction, 3-butene-1-ol is obtained.

[0009] Preferably, the cathode powder catalyst includes Cu, CuO, Cu3P, CuS, Cu(OH)2, Co, CoO, CoP, Co(OH)2, copper phthalocyanine, copper carbene or a copper single atom catalyst supported on a nitrogen-doped carbon material.

[0010] Preferably, the anode powder catalyst comprises Ir / C, Ru / C, IrO2, RuO2, nickel hydroxide nanosheets, nickel iron hydroxide nanosheets or nickel cobalt hydroxide nanosheets.

[0011] Preferably, the cathode or anode is prepared by spraying a powder catalyst, comprising:

[0012] The powdered catalyst is evenly dispersed in a solvent, and Nafion solution is added and mixed to obtain a uniformly dispersed slurry;

[0013] The slurry is sprayed onto a conductive substrate and dried to obtain a cathode or an anode;

[0014] Among them, when the powder catalyst adopts cathode powder catalyst, the prepared product is cathode; when the powder catalyst adopts anode powder catalyst, the prepared product is anode;

[0015] The solvent includes one or more of ultrapure water, ethanol, and isopropanol.

[0016] Preferably, the usage ratio of the powder catalyst, solvent and Nafion solution is (10 mg~10 g): (2 mL~2 L): (30 μL~5 mL); the mass fraction of the Nafion solution is 1-20 wt%.

[0017] Preferably, the conductive substrate comprises carbon paper, carbon cloth, conductive glass or foam metal;

[0018] The foam metal includes foam copper, foam cobalt or foam nickel.

[0019] Preferably, the cathode or anode powder catalyst is attached to the conductive substrate by an in-situ growth method to prepare the cathode or anode, comprising:

[0020] Using foamed metal as a conductive substrate, in-situ growing cathode or anode powder catalyst by impregnation, hydrothermal method, electrodeposition method or calcination method, and obtaining cathode or anode by washing and drying;

[0021] Preferably, the cathode electrolyte and the anode electrolyte are both 0.01-10 M KOH aqueous solution, 0.01-10 M KHCO3 aqueous solution, 0.01-5 M hydrochloric acid aqueous solution or 0.01-5 M sulfuric acid aqueous solution.

[0022] Preferably, for a flow-type electrolytic cell, the electrolyte flow rate is 5-500 sccm; for an H-type electrolytic cell, the electrolyte stirring speed is 200-1000 rppm;

[0023] The electrochemical method includes cyclic voltammetry, constant current method or constant voltage method.

[0024] Preferably, the concentration of the 1,4-butenediol is 0.001-5 M.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] The present invention provides 3-butene-1-ol prepared by electrocatalytic hydrodehydroxylation of 1,4-butenediol, as well as a preparation method and application thereof. This method operates at room temperature and pressure, has low energy consumption, and emits no carbon dioxide, meeting the requirements of green chemical industry. The method utilizes inexpensive 1,4-butenediol as a raw material, water as a hydrogen source, and non-precious metal catalysts such as copper and cobalt, significantly reducing the production cost of 3-butene-1-ol. The method utilizes simple and easy-to-use equipment and can be modularized. Experimental results demonstrate superior conversion, selectivity, and yield compared to those achieved under thermal catalysis, demonstrating its significant application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is the SEM image of the Cu(OH)2 nanoarray provided in Example 1.

[0028] Figure 2 This is a gas chromatogram of Example 1 after 1 hour of electrochemical reaction at -1.0 V.

[0029] Figure 3 This is Example 1, the conversion rate of 1,4-butenediol and the selectivity of 3-butene-1-ol at different voltages.

[0030] Figure 4 The performance comparison of electrocatalytic process and thermal catalytic process. DETAILED DESCRIPTION

[0031] In order to enable those skilled in the art to better understand and implement the technical solution of the present invention, the present invention is further described below with reference to specific embodiments and drawings, but the embodiments are not intended to limit the present invention.

[0032] The present invention aims to provide 3-butene-1-ol prepared by electrocatalytic 1,4-butenediol hydrodehydroxylation, as well as a preparation method and application thereof. The present invention uses electricity driven by renewable energy at room temperature and pressure, resulting in low energy consumption. In addition, the invention uses inexpensive water and 1,4-butenediol as raw materials, resulting in low cost and a safe reaction.

[0033] In order to achieve the above object, the first aspect of the present invention provides a method for preparing 3-butene-1-ol by electrocatalytic hydrodehydroxylation of 1,4-butenediol, comprising the following steps:

[0034] Adhere cathode or anode powder catalyst to the conductive substrate by adopting in-situ growth method or powder spraying method to prepare cathode or anode;

[0035] A flow electrolytic cell or an H-type electrolytic cell is assembled using the prepared cathode and anode, and a cathode electrolyte and an anode electrolyte are introduced into the cathode chamber and the anode chamber, respectively. At the same time, the raw material 1,4-butenediol is introduced into the cathode chamber. Subsequently, a three-electrode or two-electrode system is used to carry out an electrochemical hydrogenation-dehydroxylation reaction of 1,4-butenediol. After 1-2 hours of electrochemical reaction, 3-butene-1-ol is obtained.

[0036] The present invention can be carried out at room temperature and pressure, can maintain high selectivity at a high conversion rate, and uses water as a hydrogen source in an electrocatalytic manner, thus meeting the needs of green chemical industry.

[0037] Among them, the cathode powder catalyst includes Cu, CuO, Cu3P, CuS, Cu(OH)2, Co, CoO, CoP, Co(OH)2, copper phthalocyanine, copper carbene or copper single atom catalyst supported by nitrogen-doped carbon material.

[0038] The anode powder catalyst includes Ir / C, Ru / C, IrO2, RuO2, nickel hydroxide nanosheets, nickel iron hydroxide nanosheets or nickel cobalt hydroxide nanosheets.

[0039] The cathode or anode is prepared by spraying powder catalyst, including:

[0040] The powdered catalyst is evenly dispersed in a solvent, and Nafion solution is added and mixed to obtain a uniformly dispersed slurry;

[0041] The slurry is sprayed onto a conductive substrate and dried to obtain a cathode or an anode;

[0042] Among them, when the powder catalyst adopts cathode powder catalyst, the prepared product is cathode; when the powder catalyst adopts anode powder catalyst, the prepared product is anode;

[0043] The solvent includes one or more of ultrapure water, ethanol, and isopropanol.

[0044] The dosage ratio of the powder catalyst, solvent and Nafion solution is (10 mg~10 g): (2 mL~2 L): (30 μL~5 mL); the mass fraction of the Nafion solution is 1-20 wt%.

[0045] The conductive substrate includes carbon paper, carbon cloth, conductive glass or foam metal;

[0046] The foam metal includes foam copper, foam cobalt or foam nickel.

[0047] According to the present invention, a cathode or anode powder catalyst is attached to a conductive substrate by an in-situ growth method to prepare a cathode or anode, comprising:

[0048] Using foamed metal as a conductive substrate, in-situ growing cathode or anode powder catalyst by impregnation, hydrothermal method, electrodeposition method or calcination method, and then washing and drying to obtain the cathode or anode;

[0049] The cathode electrolyte and the anode electrolyte are both 0.01-10 M KOH aqueous solution, 0.01-10 M KHCO3 aqueous solution, 0.01-5 M hydrochloric acid aqueous solution or 0.01-5 M sulfuric acid aqueous solution.

[0050] For a flow-type electrolytic cell, the electrolyte flow rate is 5-500 sccm; for an H-type electrolytic cell, the electrolyte stirring speed is 200-1000 rppm;

[0051] The electrochemical method includes cyclic voltammetry, constant current method or constant voltage method.

[0052] The concentration of the 1,4-butenediol is 0.001-5 M.

[0053] It should be noted that the principle of an electrocatalytic 1,4-butenediol hydrogenation and dehydroxylation process to prepare 3-butene-1-ol is as follows: in an electrolytic cell, water in the electrolyte is used as a hydrogen source, 1,4-butenediol raw material is added to the cathode chamber, and when power is applied, the product generated at the cathode is 3-butene-1-ol.

[0054] The reaction equation for electrocatalytic hydrodehydroxylation of 1,4-butenediol is as follows:

[0055]

[0056] In order to realize the above principle, the following specific steps are adopted:

[0057] Preparation of cathode and anode The cathode and anode include a conductive metal foam on which a powder catalyst is sprayed or a catalyst is grown in situ;

[0058] The preparation method of the conductive substrate sprayed with powder catalyst is as follows: 10 mg to 10 g of cathode or anode catalyst powder is uniformly dispersed in 2 mL to 2 L of solvent, and 30 μL to 5 mL of Nafion solution is added, and the mixture is shaken in an ultrasonic bath for 10 to 120 minutes to obtain a uniformly dispersed catalyst slurry, wherein the solvent includes but is not limited to one or more of ultrapure water, ethanol, and isopropanol, and the mass fraction of the Nafion solution is 1 to 20 wt%; the catalyst slurry is sprayed onto the conductive substrate, and a conductive substrate cathode / anode sprayed with powder catalyst is obtained by drying, wherein the catalyst loading is 0.001 to 10 mg / cm 2 , the conductive substrate includes but is not limited to carbon paper, carbon cloth, conductive glass, and foam metal;

[0059] The cathode powder catalyst includes but is not limited to nanoparticles such as Cu, CuO, Cu3P, CuS, Cu(OH)2, Co, CoO, CoP, Co(OH)2, etc., molecular catalysts such as copper phthalocyanine and copper carbene, and copper single atom catalysts supported by nitrogen-doped carbon materials; the anode powder catalyst includes but is not limited to Ir / C, Ru / C, IrO2, RuO2, nickel hydroxide nanosheets, nickel iron hydroxide nanosheets, nickel cobalt hydroxide nanosheets, etc.

[0060] The preparation method of the conductive foam metal for in-situ growth of the catalyst is as follows: using the conductive foam metal as a substrate, in-situ growing the catalyst by impregnation, hydrothermal method, electrodeposition method or calcination method, and obtaining the final electrode by cleaning and drying treatment, wherein the foam metal includes but is not limited to foam copper, foam cobalt, and foam nickel; taking the growth of Cu(OH)2 on foam copper as an example of a cathode, the specific preparation method is as follows: ultrasonically cleaning the foam copper with 1 M dilute hydrochloric acid, acetone, and anhydrous ethanol in sequence, drying it with a nitrogen flow, immersing the treated foam copper in a solution prepared by ammonium persulfate and sodium hydroxide, standing for half an hour, rinsing with ultrapure water, and naturally air-drying, wherein the concentration of the ammonium persulfate is 0.04 M, and the concentration of the sodium hydroxide is 0.8 M.

[0061] Assembly of the electrolytic cell: The electrolytic cell includes a flow-type electrolytic cell and an H-type electrolytic cell. When the electrolytic cell is a flow-type electrolytic cell, the specific assembly steps are: assembling the electrolytic cell in the order of an end plate, the cathode prepared above, an ion exchange membrane, an anode, and an end plate, wherein the ion exchange membrane includes but is not limited to one of a proton exchange membrane and an anion exchange membrane; an electrolyte is passed through the cathode chamber and the anode chamber, and a 1,4-butenediol raw material is added to the cathode, and the electrolyte flow rate is 5-500 sccm;

[0062] When the electrolytic cell is an H-type electrolytic cell, the specific assembly steps are as follows: separating the cathode chamber and the anode chamber with an ion exchange membrane. The ion exchange membrane includes but is not limited to one of a proton exchange membrane and an anion exchange membrane. Electrolyte is added to the cathode chamber and the anode chamber, and 1,4-butenediol raw material is simultaneously added to the cathode chamber while continuously stirring at a rotation speed of 200-1000 rppm.

[0063] The electrolyte includes but is not limited to 0.01-10 M KOH aqueous solution, 0.01-10 M KHCO3 aqueous solution, 0.01-5 M hydrochloric acid aqueous solution, 0.01-5 M sulfuric acid aqueous solution, 0.01-5 M KCl aqueous solution, 0.01-10 M KOH aqueous solution;

[0064] The concentration of the 1,4-butenediol raw material is 0.001-5 M.

[0065] The electrocatalytic hydrodehydroxylation reaction is carried out using a three-electrode system or a two-electrode system. The electrolytic cell is operated by an electrochemical method, and the reaction products are tested by liquid chromatography to determine the conversion rate of 1,4-butenediol, the selectivity and yield of 3-butene-1-ol. The electrochemical method includes but is not limited to cyclic voltammetry, constant current method, and constant voltage method.

[0066] It should be noted that the experimental methods used in the present invention are all conventional methods unless otherwise specified; the reagents and materials used are all commercially available unless otherwise specified.

[0067] Example 1

[0068] (1) Preparation of in situ grown Cu(OH)2 nanoarrays on copper foam: a. Ultrasonicate the copper foam with 1 M dilute hydrochloric acid, acetone, and anhydrous ethanol solutions for 5 min, respectively, and blow dry with nitrogen gas; b. Immerse the copper foam in a solution of 0.04 M ammonium persulfate and 0.8 M sodium hydroxide dissolved in deionized water. After standing for 30 min, remove the copper foam sample, rinse it with deionized water several times, and air dry it naturally. Figure 1 Shown is the SEM image of the Cu(OH)2 nanoarray provided in this embodiment.

[0069] (2) Assembly of a flow-type electrolytic cell: Cu(OH)2 grown in situ on copper foam was used as the cathode, nickel foam was used as the anode, and Hg / HgO was used as the reference electrode. Both the catholyte and the anolyte were 1 M KOH solutions at a flow rate of 100 sccm. The cathode and anode chambers were separated by a Fumasep FAB-PK-130 anion exchange membrane. 0.5 M of the reactant 1,4-butenediol was added to the catholyte.

[0070] (3) Electrochemical hydrogenation and dehydroxylation performance: Electrochemical performance testing was performed using a three-electrode system. The catalytic activity of the Cu(OH)2 catalyst was tested using a constant potential method. After one hour of reaction, the product, 3-butene-1-ol, was analyzed by liquid chromatography.

[0071] Example 2

[0072] (1) Preparation of Cu nanoparticle catalyst sprayed on carbon fiber paper: 80 mg of Cu nanoparticle catalyst powder was dispersed in 20 mL of ethanol, and then 100 μL of Nafion solution (5 wt%) was added, ultrasonically dispersed for 60 min, and sprayed onto carbon fiber paper.

[0073] (2) Assembly of a flow-type electrolytic cell: The carbon fiber paper sprayed with Cu nanoparticles was used as the cathode, nickel foam was used as the anode, and Hg / HgO was used as the reference electrode. The cathode and anode electrolytes were both 1 M KOH solutions at a flow rate of 100 sccm. The cathode and anode compartments were separated by a Fumasep FAB-PK-130 anion exchange membrane. 0.5 M of the reactant 1,4-butenediol was added to the cathode electrolyte.

[0074] (3) Electrochemical hydrogenation and dehydroxylation performance: Electrochemical performance testing was performed using a three-electrode system. The catalytic activity of the carbon fiber paper-sprayed Cu nanoparticle catalyst was tested using a constant potential method. After one hour of reaction, the product, 3-butene-1-ol, was analyzed by liquid chromatography.

[0075] Example 3

[0076] (1) Preparation of in situ grown Cu nanowire arrays on copper foam: a. Ultrasonic treatment of copper foam with 1 M dilute hydrochloric acid, acetone and anhydrous ethanol solution for 5 min respectively, and then drying with nitrogen flow; b. Immerse copper foam in a solution of 0.04 M ammonium persulfate and 0.8 M sodium hydroxide dissolved in deionized water. After standing for 30 min, take out the copper foam sample, rinse it with deionized water several times and air-dry it to obtain Cu(OH)2 nanowire arrays; c. Reduce it in a tube furnace at 300 °C in an atmosphere of H2 / Ar mixed gas (4:96) to obtain in situ grown Cu nanowire arrays on copper foam.

[0077] (2) Assembly of a flow-type electrolytic cell: A Cu nanowire array grown in situ on copper foam was used as the cathode, Hg / HgO as the reference electrode, and nickel foam as the anode. Both the cathode and cathode electrolytes were 1 M KOH solutions at a flow rate of 100 sccm, separated by a Fumasep FAB-PK-130 anion exchange membrane. 0.5 M of the reactant 1,4-butenediol was added to the cathode electrolyte.

[0078] (3) Electrochemical hydrogenation and dehydroxylation performance: Electrochemical performance testing was performed using a three-electrode system. The catalytic activity of the in situ grown Cu nanowire array on copper foam was tested using a constant potential method. After 1 hour of reaction, the product 3-butene-1-ol was analyzed by liquid chromatography.

[0079] Example 4

[0080] (1) Preparation of CuO nanoparticle catalyst sprayed on carbon cloth: 80 mg of CuO nanoparticle catalyst powder was dispersed in 40 mL of isopropanol, and then 100 μL of Nafion solution (5%) was added. The mixture was stirred and ultrasonically dispersed for 60 min and then sprayed onto the carbon cloth.

[0081] (2) Assembly of a flow-type electrolytic cell: A CuO nanoparticle catalyst sprayed onto carbon cloth was used as the cathode of the electrolytic cell, and nickel foam was used as the anode. The cathode and anode electrolytes were both 1 M KHCO3 solutions at a flow rate of 100 sccm. The cathode and anode compartments were separated by a Nafion 117 proton exchange membrane. 0.5 M of the reactant 1,4-butenediol was added to the cathode electrolyte.

[0082] (3) Electrochemical hydrogenation and dehydroxylation performance: Electrochemical performance testing was performed using a two-electrode system. The catalytic activity of the CuO nanoparticles was tested using a constant potential method. After one hour of reaction, the product, 3-butene-1-ol, was analyzed by liquid chromatography.

[0083] Example 5

[0084] (1) Preparation of carbene copper nanoparticle catalyst sprayed on copper foam: Carbene copper nanoparticles were prepared by dispersing 80 mg of carbene copper nanoparticle catalyst powder in 20 mL of isopropanol, and then adding 100 μL of Nafion solution (5%). The mixture was stirred and ultrasonically dispersed for 60 min and then sprayed onto the copper foam.

[0085] (2) Assembly of a flow-type electrolytic cell: A copper foam coated with carbene nanoparticle catalyst was used as the cathode, Hg / HgO was used as the reference electrode, and nickel foam was used as the anode. The cathode and cathode electrolytes were both 1 M KOH solutions at a flow rate of 100 sccm, separated by a Fumasep FAB-PK-130 anion exchange membrane. 0.5 M of the reactant 1,4-butenediol was added to the cathode electrolyte.

[0086] (3) Electrochemical hydrogenation and dehydroxylation performance: Electrochemical performance testing was performed using a three-electrode system. The catalytic activity of the copper carbene catalyst was tested using a constant potential method. After 1 hour of reaction, the product 3-butene-1-ol was analyzed by liquid chromatography.

[0087] Example 6

[0088] (1) Preparation of copper phthalocyanine nanoparticle catalyst sprayed on carbon cloth: 80 mg of copper phthalocyanine nanoparticle catalyst powder was dispersed in 20 mL of isopropanol, and then 100 μL of Nafion solution (5%) was added. The mixture was stirred and ultrasonically dispersed for 60 min and then sprayed onto the copper foam.

[0089] (2) Assembly of a flow-type electrolytic cell: A copper phthalocyanine nanoparticle catalyst was sprayed onto carbon cloth as the cathode, Hg / HgO as the reference electrode, and nickel foam as the anode. Both the cathode and cathode electrolytes were 1 M KOH solutions at a flow rate of 100 sccm, separated by a Fumasep FAB-PK-130 anion exchange membrane. 0.5 M of the reactant, 1,4-butenediol, was added to the cathode electrolyte.

[0090] (3) Electrochemical hydrogenation and dehydroxylation performance: Electrochemical performance testing was performed using a three-electrode system. The catalytic activity of the copper phthalocyanine catalyst was tested using a constant potential method. After 1 hour of reaction, the product 3-butene-1-ol was analyzed by liquid chromatography.

[0091] Example 7

[0092] (1) Preparation of in situ grown Cu(OH)2 nanowire arrays on copper foam: a. Ultrasonicate the copper foam with 1 M dilute hydrochloric acid, acetone, and anhydrous ethanol solutions for 5 min, respectively, and blow dry with a nitrogen stream; b. Immerse the copper foam in a solution of 0.04 M ammonium persulfate and 0.8 M sodium hydroxide dissolved in deionized water. After standing for 30 min, remove the copper foam sample, rinse it several times with deionized water, and air-dry it naturally.

[0093] (2) H-type electrolytic cell assembly: Cu(OH)2 grown in situ on copper foam was used as the cathode, nickel foam was used as the anode, and Hg / HgO was used as the reference electrode. Both the catholyte and the anolyte were 1 M KOH solutions. The stirring rate was 300 rppm, and the cathode and anode compartments were separated by a Fumasep FAB-PK-130 anion exchange membrane. 0.5 M of the reactant 1,4-butenediol was added to the catholyte.

[0094] (3) Electrochemical hydrogenation and dehydroxylation performance: Electrochemical performance testing was performed using a three-electrode system. The catalytic activity of the copper hydroxide catalyst was tested using a constant potential method. After one hour of reaction, the product, 3-butene-1-ol, was analyzed by liquid chromatography.

[0095] Example 8

[0096] (1) Preparation of cobalt foam sprayed with cobalt nanoparticle catalyst: 80 mg of cobalt nanoparticle catalyst powder was dispersed in 20 mL of isopropanol, and then 100 μL of Nafion solution (5%) was added. The mixture was stirred and ultrasonically dispersed for 60 min and then sprayed onto the cobalt foam.

[0097] (2) H-type electrolytic cell assembly: Cobalt foam sprayed with cobalt nanoparticle catalyst served as the cathode, nickel foam served as the anode, and the cathode and cathode electrolytes were both 1 M KOH solutions. The stirring rate was 300 rppm, and the cells were separated by a Fumasep FAB-PK-130 anion exchange membrane. 0.5 M of the reactant 1,4-butenediol was added to the cathode electrolyte.

[0098] (3) Electrochemical hydrogenation and dehydroxylation performance: Electrochemical performance testing was performed using a two-electrode system. The catalytic activity of the cobalt nanoparticle catalyst was tested using a constant potential method. After one hour of reaction, the product, 3-butene-1-ol, was analyzed by liquid chromatography.

[0099] Example 9

[0100] (1) Preparation of in situ grown CuS on copper foam: a. Ultrasonic treatment of copper foam with 1 M dilute hydrochloric acid, acetone and anhydrous ethanol solution for 5 min respectively, and then drying with nitrogen flow; b. Immerse copper foam in a solution of 0.04 M ammonium persulfate and 0.8 M sodium hydroxide dissolved in deionized water. After standing for 30 min, take out the copper foam sample, rinse it with deionized water several times and air-dry it naturally; c. Sulfurization was carried out in a tube furnace at a temperature of 300 °C for 2 h to obtain in situ grown CuS on copper foam.

[0101] (2) H-type electrolytic cell assembly: CuS foam was in situ grown as the cathode, nickel foam was used as the anode, and the cathode and cathode electrolytes were both 1 M KOH solutions. The stirring rate was 300 rppm, and the cells were separated by a Fumasep FAB-PK-130 anion exchange membrane. 0.5 M of the reactant 1,4-butenediol was added to the cathode electrolyte.

[0102] (3) Electrochemical hydrogenation and dehydroxylation performance: Electrochemical performance testing was performed using a two-electrode system. The catalytic activity of the CuS catalyst was tested using a constant potential method. After 1 hour of reaction, the product 3-butene-1-ol was analyzed by liquid chromatography.

[0103] In order to illustrate the performance of the catalyst used in the method for preparing 3-butene-1-ol provided by the present invention, the specific evaluation results of the catalyst are shown in Table 1.

[0104] Table 1 Catalyst specific evaluation results

[0105]

[0106] As can be seen from Table 1, both copper-based materials and cobalt-based materials can achieve a 1,4-butenediol conversion rate of more than 84% and a 3-butene-1-ol selectivity of more than 80%, proving that 3-butene-1-ol can be prepared by hydrogenation and dehydroxylation of 1,4-butenediol.

[0107] Figure 1 The SEM image of the Cu(OH)2 nanoarray provided in Example 1; Figure 1 It can be seen that the Cu(OH)2 nanowire array is evenly loaded on the copper foam, with a diameter of about 100-200 nm.

[0108] Figure 2 This is a gas chromatogram of Example 1 after 1 hour of electrochemical reaction at -1.0 V. It can be seen from the figure that after the electrochemical reaction, the peak of 1,4-butenediol decreases, and the peaks of 3-butene-1-ol, 1,4-butanediol and n-butanol appear, and the peak of 3-butene-1-ol accounts for the largest proportion, proving the feasibility of preparing 3-butene-1-ol by hydrodehydroxylation of 1,4-butenediol.

[0109] Figure 3 For Example 1, the conversion rate of 1,4-butenediol and the selectivity of 3-butene-1-ol at different voltages; it can be seen from the figure that the conversion rate of 1,4-butenediol increases from 20.7% to 98.0% at -0.5 V to -1.1 V, and the selectivity of 3-butene-1-ol is greater than 61.6% in the entire voltage application window.

[0110] Figure 4 This figure compares the performance of electrocatalytic and thermal catalytic processes; the electrocatalytic process is Example 1, and the thermal catalytic process is the dehydration of 1,4-butanediol. The reaction temperature is 360-600°C, and the catalysts are shown in the figure. As can be seen from the figure, the yield of 3-butene-1-ol in the electrocatalytic process is higher than that of the catalysts listed in the thermal catalytic process, demonstrating the advantages of electrocatalysis.

[0111] In summary, the present invention uses 1,4-butenediol as a reactant and efficiently prepares 3-butene-1-ol through a hydrogenation and dehydroxylation reaction at room temperature and normal pressure in an electrocatalytic manner, thereby solving the key problems faced by traditional synthesis routes, such as high temperature, high pressure, complex process flow, and many by-products.

[0112] The present invention describes preferred embodiments and their effects. However, those skilled in the art, once informed of the basic inventive concept, may make additional changes and modifications to these embodiments. Therefore, it is intended that the appended claims be interpreted to include the preferred embodiments as well as all changes and modifications that fall within the scope of the invention.

[0113] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing 3-butene-1-ol by electrocatalytic hydrodehydroxylation of 1,4-butenediol, characterized in that: The following steps are involved: Adhere cathode or anode powder catalyst to the conductive substrate by adopting in-situ growth method or powder spraying method to prepare cathode or anode; A flow electrolytic cell or an H-type electrolytic cell is assembled using the prepared cathode and anode, and a catholyte and an anolyte are introduced into the cathode chamber and the anode chamber, respectively. Simultaneously, a raw material, 1,4-butenediol, is introduced into the cathode chamber. Subsequently, an electrochemical hydrogenation-dehydroxylation reaction of 1,4-butenediol is carried out using a three-electrode or two-electrode system. After an electrochemical reaction of 1 to 2 hours, 3-butene-1-ol is obtained. The cathode powder catalyst includes Cu, CuO, Cu3P, CuS, Cu(OH)2, Co, CoO, CoP, Co(OH)2, copper phthalocyanine, copper carbene or copper single atom catalyst supported by nitrogen-doped carbon material.

2. The method for preparing 3-butene-1-ol by electrocatalytic hydrodehydroxylation of 1,4-butenediol according to claim 1, characterized in that: The anode powder catalyst includes Ir / C, Ru / C, IrO2, RuO2, nickel hydroxide nanosheets, nickel iron hydroxide nanosheets or nickel cobalt hydroxide nanosheets.

3. The method for preparing 3-butene-1-ol by electrocatalytic hydrodehydroxylation of 1,4-butenediol according to claim 1, characterized in that: The cathode or anode is prepared by spraying powder catalyst, including: The powdered catalyst is evenly dispersed in a solvent, and Nafion solution is added and mixed to obtain a uniformly dispersed slurry; The slurry is sprayed onto a conductive substrate and dried to obtain a cathode or an anode; Among them, when the powder catalyst adopts cathode powder catalyst, the prepared product is cathode; when the powder catalyst adopts anode powder catalyst, the prepared product is anode; The solvent includes one or more of ultrapure water, ethanol, and isopropanol; The conductive substrate includes carbon paper, carbon cloth, conductive glass or foam metal; The foam metal includes foam copper, foam cobalt or foam nickel.

4. The method for preparing 3-butene-1-ol by electrocatalytic hydrodehydroxylation of 1,4-butenediol according to claim 3, characterized in that: The dosage ratio of the powder catalyst, solvent and Nafion solution is (10 mg~10 g): (2 mL~2 L): (30 μL~5 mL); the mass fraction of the Nafion solution is 1-20 wt%.

5. The method for preparing 3-butene-1-ol by electrocatalytic hydrodehydroxylation of 1,4-butenediol according to claim 3, characterized in that: The cathode or anode is prepared by attaching a cathode or anode powder catalyst to a conductive substrate using an in-situ growth method, comprising: Using foam metal as a conductive substrate, cathode or anode powder catalyst is grown in situ through impregnation, hydrothermal method, electrodeposition method or calcination method, and the cathode or anode is obtained through cleaning and drying treatment.

6. The method for preparing 3-butene-1-ol by electrocatalytic hydrodehydroxylation of 1,4-butenediol according to claim 1, characterized in that: The cathode electrolyte and the anode electrolyte are both 0.01-10 M KOH aqueous solution, 0.01-10 M KHCO3 aqueous solution, 0.01-5 M hydrochloric acid aqueous solution or 0.01-5 M sulfuric acid aqueous solution; the concentration of the 1,4-butenediol is 0.001-5 M.

7. The method for preparing 3-butene-1-ol by electrocatalytic hydrodehydroxylation of 1,4-butenediol according to claim 1, characterized in that: For a flow-type electrolytic cell, the electrolyte flow rate is 5-500 sccm; for an H-type electrolytic cell, the electrolyte stirring speed is 200-1000 rppm; The electrochemical method includes cyclic voltammetry, constant current method or constant voltage method.

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